【解决办法】绘制entity实体线，构建自定义动态纹理材质color:材质颜色，duration:纹理流动循环周期，texture2D(image, vec2(fract(st.s5.0-time1.0), st.t))：纹理运动方向及速度，最后给实体线赋予动态材质贴图，例如：river = viewer.entities.add({
name : 'river',
polyline : {
positions : new Cesium.Cartesian3.fromDegreesArrayHeights(positions),
width: 20,
followSurface : true,
material : new Cesium.PolylineTrailLinkMaterialProperty(Cesium.Color.SKYBLUE,10000),
clampToGround: true,
distanceDisplayCondition: new Cesium.DistanceDisplayCondition(0, 30000)
}
});
动态纹理代码可以参考博客：
https://blog.csdn.net/supermapsupport/article/details/118387144
